In ZWCAD, you can use the following way to set the style of the multi-line. The method is finding the Multi-line Style option in the format menu and creating a new style firstly. Then naming the new style and setting it in accordance with your requirements. After setting, confirm and click OK.
Multi-line style command: [MLSTYLE]
More style line location: [Form] - [Multi-line Style]
Multi-line command: "ML".